If you would like to have on Board self serve laundry, Please write in your need for the "Non Revenue" service on the ships. I have not used the self serve laundry on short cruises, but I plan on using the laundry 1 time on the long cruises. I do not trust the Ship's Laundry Service with my all cotton tops.
Cruise line are seeing the self serve laundry as a Non-revenue space that can be changed into revenue generating cabins.